fix: Alias --es-module-specifier-resolution to --experimental-specifier-resolution for Node 12 compatibility

[nguyensomniac]

Context here: #1007 (comment)

The --es-module-specifier-resolution flag was introduced in Node 12. With the release of Node 13, the flag was renamed to --experimental-specifier-resolution, with --es-module-specifier-resolution acting as an alias to the new name.

This fix aliases the --es-module-specifier-resolution flag in older versions of node, so that module resolution acts as expected. I also changed what seems to be a dead branch in the esm-usage-example directory.

I tested this with node 12, 13, and 14 and all seems to be working as expected.

[codecov]

Codecov Report

Merging #1122 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1122   +/-   ##
=======================================
  Coverage   79.32%   79.32%           
=======================================
  Files           7        7           
  Lines         711      711           
  Branches      158      158           
=======================================
  Hits          564      564           
  Misses         90       90           
  Partials       57       57           

Flag	Coverage Δ
#node_10	76.28% <ø> (ø)
#node_12_15	76.63% <ø> (ø)
#node_12_16	76.63% <ø> (ø)
#node_13	79.04% <ø> (ø)
#node_14	79.04% <ø> (ø)
#typescript_2_7	78.90% <ø> (ø)
#typescript_latest	78.19% <ø> (ø)
#typescript_next	78.05% <ø> (ø)
#ubuntu	79.04% <ø> (ø)
#windows	79.18% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
dist-raw/node-options.js	78.78% <ø> (ø)

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[coveralls]

Coverage increased (+0.9%) to 86.95% when pulling bf7e824 on nguyensomniac:lily/esm-alias into 41e7109 on TypeStrong:master.

[cspotcode]

@nguyensomniac thanks, seems like a simple change, and thanks for adding a test.

Node's docs do not mention the older flag name: --es-module-specifier-resolution
https://nodejs.org/docs/latest-v12.x/api/esm.html#esm_resolution_algorithm

Was the flag renamed during node 12's lifetime?

[ExE-Boss]

Was the flag renamed during node 12's lifetime?

Yes, it was.

Probably even long‑ish before v12 became LTS.

[nguyensomniac]

Ah, you're correct. Running node --help looks like it was renamed after 12.15

[cspotcode]

Thanks! I added a comment to remind me when this flag was changed.

This will be published to npm after I merge #1121; until then, you can install directly from git. I always forget the syntax, but I think it's npm install github:TypeStrong/ts-node#master